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Inside the Scorpio Engine: the processor architecture deep dive
- Thread starter Space_nut
- Start date
Can someone explain this fp16 and fp32 stuff to me like I'm five?
I'm surprised people are giving any relevance to this discussion... but I want to know if this actually matters.
Is it confirmed that Scorpio doesn't have fp16?
If yes, does it mean it isn't a big leap over PS4 Pro anymore? And why can't Microsoft just add fp16 themselves? It requires special hardware?
Or, can we still comfortably say Scorpio is a beast and all the other engineering put into the console deserves high praise?
I'm surprised people are giving any relevance to this discussion... but I want to know if this actually matters.
Is it confirmed that Scorpio doesn't have fp16?
If yes, does it mean it isn't a big leap over PS4 Pro anymore? And why can't Microsoft just add fp16 themselves? It requires special hardware?
Or, can we still comfortably say Scorpio is a beast and all the other engineering put into the console deserves high praise?
funkystudent
Member
Unless PS4 momentum stops in its tracks I think we are in for few years of PS4. Maybe 2019 for PS5? I could also see them leaving it till 2020 depending on if sales keep going well.
But I'd be shocked if MS didnt also have a new box right around the PS5 launch too, if now sooner.
Hawk269
Member
I wish you didn't ask this. This is going to make things go south really fast. Hold on to your butt's guys...thread is about to go nuclear.
I'd assume it'll be 2020. It's still selling a ton.
nekkid
It doesn't matter who we are, what matters is our plan.
Make sure you speak to onQ123. Otherwise you run the risk of having your excitement going unchecked.
BritBloke916
Member
Indeed. For me, the primary reason for Jaguar's use in Scorpio is that there simply was no viable alternative. It's the best that MS could do for the launch date that they felt they needed to hit, but the timing of that launch date ruled out anything more than a modest CPU boost over the Pro.
Oh for fuc--
It's how many digits of a floating point number the GPU can use during calculations. A bigger number means that any calculations will be more accurate, but it's also slower. In scientific use, 32bit is usually not accurate enough, they actually use 64bit or higher. But for real-time graphics, 32bit is occasionally too much acccuracy (or more accurately, an unnecessary level of accuracy), and you wont notice the difference if you're half as a precise, i.e. use a 16bit FP number. But only some of the time.
What are you even talking about?
Also cost.
BritBloke916
Member
Absolutely.
Leyasu
Banned
Of course it's helpful, just ask one. Pro is now a more powerful machine...
Sad Affleck
Member
I can't decide if OnQ123 doesn't understand technology at all yet keeps posting about it or if he does understand technology and posts with the intention of misleading less knowledgeable posters. Either way it is in very bad taste.
Liabe Brave
Member
FP32 and FP16 describe different levels of precision for floating-point numbers. Basically any hardware can use either format, but older hardware moved the smaller format at the same speed as the bigger one. Some new hardware, including AMD's upcoming Vega cards, PS4 Pro, and Switch can essentially "carpool" two FP16 numbers into the FP32 space, meaning they can be moved around twice as fast.
Scorpio definitely does not have this hardware, and cannot be updated via software. They can still use FP16, but it won't run any faster than FP32. This might mean that games which take advantage of the Pro hardware will not be quite as far behind on performance as the raw TFLOPS numbers indicate. But we have yet to see any evidence.
Scorpio is still the most powerful console ever made, and should perform better than Pro almost all the time. It's well-engineered hardware, though it doesn't seem to be quite as specialized and unique as some thought.
Self_Destructive
Member
Well, he's not saying anything other than PS4 Pro's peak theoretical performance at FP32 is 4.2TF, and at FP16 it's 8.4TF. He's not wrong and not misunderstanding things.
If I was trying to mislead people I would post the numbers without context. each & every time that I have posted about PS4 Pro peak performance being 8.4TF I let it be known that it is fp16.
Head.spawn
Junior Member
I'd just like to know the significance as far as final results, that would make it worth making fp16 your focal point in every thread.
Do you expect it to lead to a big performance change?
Do you expect it to lead to a big performance change?
dr_rus
Member
Yes.
No, it is still a big leap over PS4 Pro. Most modern graphics calculations require FP32 and will not be able to work to the same result in FP16. The amount of performance a game can get from using double speed FP16 shader calculations is anyone's guess at the moment but it will most definitely not be even close to 2X (my guess would be +25% at best).
Double speed FP16 requires different shader processors which are more complex compared to just straight FP32 ones so you are loosing some FP32 performance in the same power/area if you want to have double rate FP16 in your chip. It may well be that since Scorpio is a supercharged Xbox One MS didn't see much benefit in using FP16x2 on it as all software have to be specifically optimized for Xbox One's h/w without FP16x2 anyway.
It is worth noting that all modern GCN GPUs starting with GCN3 support FP16 calculations at the same speed as FP32 - but on such GPUs you get less LDS/register pressure due to less data being used during FP16 calculations and this alone can lead to significant speed ups, even without the double rate of calculations themselves. Frostbite examples are on the previous pages.
I have to agree here but I think as soon as we See real Scorpio ingame footage all this gibberish will stop
Cant wait!
Or MS looked at all that tech an decided it wasn't necessary for their true 4K goals. Has anybody call to carpet these "lazy developers" for not using the Pro's ddr FP16 secrete sauce to get native 4K on Pro with demanding games?
To be fair, he's not talking about the relevance of FP16, just that the Pro is 8.4TF FP16
cartoon_soldier
Member
All this info. All some people caught is no support for 2xFP16 calculations.
In bad taste? Lol. Lighten up dude. It's not that serious.
It's probably 99% about you guys responding to it every time. Technically he's correct.
All of them
franklyshankly
Member
Tripolygon
Banned
But this is the only new info in the whole article. Everything else has been said before.
To be honest, people have been dogpiling on OnQ123 for months, and every single time they try to discredit him using total nonsense and factual inaccuracy. He is arguably being pedantic, and he probably brings it up more than it deserves, but, his posts are almost always more valid than those trying to criticise him.
I guarantee you, if people weren't constantly responding to it, he'd end up reiterating it less.
SEGAvangelist
Member
He argued that Scorpio might be 6TF using FP16... a 3TF console a year after PS4 Pro.
They all support fp16 it's RPM / double rate fp16 that Pro/Vega bring to the table.
Colbert
Banned
Technically he is correct and practically the usage of it limited if you already have the spec to do 4K without it.
So in case of PS4 Pro they need it to get nearer to or achieve 4K because of the lack of memory bandwidth and and GPU spec.
MS decided against it as they don't need it - they have enough GPU spec and memory speed - and favored dynamic color compression which benefits their requirements the most.
Its all check and balances based on the actual requirements and the targets you want to achieve.
franklyshankly
Member
That's kind of a pedantic distinction in this discussion isn't it?
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
Do what at 4k, though?
No I argued that we couldn't just go by the flops number without context because 6TF could mean 6TF fp32 or it could mean 6tf fp16 because some of the big GPUs was starting to use double speed fp16 like the mobile GPUs.
SEGAvangelist
Member
Saying that suggests it is possible MS was being misleading with the 6TF number during the Scorpio reveal, which was a ridiculous idea to begin with.
Right, so as this generation progresses, and these mid-gen refreshes are considered, the actual percentage of devices that support double rate fp16 is probably the most important fact in how widespread it will/ can be used.
Colbert
Banned
good point: "the calculations in a native 4K render pipeline".
touché. but no.
blu
Wants the largest console games publisher to avoid Nintendo's platforms.
Again, a pipeline doing what? Playing tetris? Playing today's games at 4k? Playing next-gen games?
'Cause we have a few consoles 'doing native 1080p', and yet, well, you get the point.
Leyasu
Banned
Why did they include checkerboard, if the gpu is 8.4tf?
I'm guessing you're not that familiar with the graphics pipeline, but I can assure you, as a graphics programmer, there will be places in any pipeline where FP16 is sufficient, and therefore, double rate FP16 is advantageous. The output resolution isn't really that relevant.
Double rate FP16 quite obviously isn't necessary for native 4K. It can still help do it slightly faster, which gives you more room for other things.
Or they went overboard with the technique they've been touting involving profiling existing games to find out how best to run them faster. All existing Xbox One titles using FP32 wouldn't benefit at all from double rate FP16, so it wouldn't be a priority if that's their sole focus.
I've always warned about assuming FP16 is widely applicable and completely agree that you won't get anything lik double the performance in practice. 10-15% sounds about right, which is enough to cut into the Scorpio's performance lead but not erase it entirely.
dragonelite
Member
Its all mental gymnastics for the console war, kinda like 200+ Gb/s bandwidth Esram could achieve when reading and writing data every 7/8 cycles and would certainly allow the x1 to close the gap between ps4.
FP16 datatype its self is interesting from what i could gather on Beyond3D given you can pack more of that data in the caches and dramatically reduce the time the compute units are waiting for the requested data.
Liabe Brave
Member
No, RPM is definitely not necessary to get many Xbox One games to native 4K on Scorpio. But its absence might potentially mean some 900p games don't make it there. And it could lead to less separation between PS4 Pro and Scorpio on multiplats. It's only a bonus, only applicable in some cases...but why would Microsoft choose to forego even more advantage? It's an interesting question.
But considering that Pro and Scorpio are separated by less than 50% overall, Pro alone getting even a 25% boost (or 20, or 15...) is very significant.
No, not really. As previously posted, FP16 has already been in use for plenty of stuff for years, because it provides some benefits even without packed math. Those elements will now be capable of providing even more performance boost on Pro (and Switch).
Colbert
Banned
You know that in a frame you do several render passes to build a single frame which is seen as a "pipeline"? Before I write my ass a picture tells more than thousands words (this is one example of a pipeline as those are different from game to game):
Clear enough now?
I did not say it hasn't any advantage if you look into my original statement, I only said MS saw not that much advantage for them as they think they don't need it and they opted instead for other things important to them like DCC. But again, FP16 is not suitable to all calculations that you may need to do your render passes as the precision might be to low hence I said the benefits are limited to the areas FP16's precision is not an issue.
Edit:
Reading all the articles and MS repeats to pointing to the fact they researched the current engines behavior before deciding on the final silicon I am sure this was a very informed decision they made against the VEGA FP16 double rate feature.
That's why I think not having FB16 double rate is a non-issue for Scorpio.
Clear
CliffyB's Cock Holster
Its not, but checkerboarding is a technique that can benefit from fp16 computation. So its a useful feature.
About this fp16 debate we have going on right now.
I look at it like this: just based on the specs of both consoles, its probably needed for the Pro and not so much for the Scorpio.
But about the 8tf thing, Cerny mentioned it in this article:
Been saying this from the get go when Scorpio news released recently, anybody keeping up with the Pro would have already knew this.
All this means is that the Pro is a decent machine even with the Scorpio having better specs. Thats all.
That said, it is interesting why its not included in the Scorpio.
Ok, this is news to me. Switch to huh. Interesting.....
I look at it like this: just based on the specs of both consoles, its probably needed for the Pro and not so much for the Scorpio.
But about the 8tf thing, Cerny mentioned it in this article:
Been saying this from the get go when Scorpio news released recently, anybody keeping up with the Pro would have already knew this.
All this means is that the Pro is a decent machine even with the Scorpio having better specs. Thats all.
That said, it is interesting why its not included in the Scorpio.
Ok, this is news to me. Switch to huh. Interesting.....
Isn't he just talking about what kind of games you expect Scorpio to run at native 4k?
(Xbox One @4k? More complex games? Less etc)